Possible bug related to stm and exceptions

[Simon Marlow]

On 17/10/2013 03:01, Andreas Voellmy wrote:
> Hi all,
>
> I have a program that uses STM heavily and also performs lots of foreign
> calls. I've noticed that sometimes the program uses 100% CPU
> indefinitely and uses lots of memory - I see it go up to about 5GB
> before I kill it. I've grabbed some preliminary samples of stack traces
> and see lots stm related stuff (e.g. lots of stg_atomically_frame_info
> and stmCommitTransaction entries).  I can pretty reliably get the
> behavior to happen now by closing a socket that my Haskell program is
> trying to recv from. When this causes an exception to be raised
> (something like "recv: resource vanished (Connection reset by peer)") ,
> then this behavior gets triggered.  I haven't pinned down the bug yet,
> but I'm suspecting it is STM related - somehow the exception causes some
> STM transaction to go wrong.
>
> Are there any known bugs that sound similar to this?
>
> BTW, this is with GHC 7.6.3 from a recent HP release on OS X.

Please create a ticket and dump all the information you have in it. 
There might be something we can tell from the stack trace, but if not 
we'll need a way to reproduce it.

Cheers,
Simon